1. IntroductionCS-4513 D-term 20081 Introduction CS-4513 Distributed Computing Systems (Slides include materials from Operating System Concepts, 7 th ed., by Silbershatz, Galvin, & Gagne, Distributed Systems: Principles & Paradigms, 2 nd ed. By Tanenbaum and Van Steen, and Modern Operating Systems, 2 nd ed., by Tanenbaum)

2. IntroductionCS-4513 D-term 20082 Outline for Today Introduction to CS-4513 What is “Distributed Computing” –An example of a distributed computation Remote Procedure Call Assignment of Project #1

3. IntroductionCS-4513 D-term 20083 CS-4513, Distributed Systems Continuation of CS-3013, Operating Systems –File Systems No coverage in A- or C-Term CS-3013 (2007-2008) Distributed System Topics –Remote Procedure Call –Naming –Security and Encryption –Atomic Transactions –…

4. IntroductionCS-4513 D-term 20084 Four Principal Abstractions Implemented by almost all Operating Systems Processes and Threads Abstracts notion of “processor” Concurrency and synchronization Virtual Memory Address space in which a process “thinks” Physical memory is cache of virtual memory Files Named, persistent storage of information Sockets and connections Conversations among processes/threads across a network

5. IntroductionCS-4513 D-term 20085 Four Principal Abstractions Implemented by almost all Operating Systems Processes and Threads Abstracts notion of “processor” Concurrency and synchronization Virtual Memory Address space in which a process “thinks” Physical memory is cache of virtual memory Files Named, persistent storage of information Sockets and connections Conversations among processes/threads across a network OS course This courseCS-4514

6. IntroductionCS-4513 D-term 20086 CS-4513, Distributed Systems Continuation of CS-3013, Operating Systems –File Systems No coverage in A- or C-Term CS-3013 (2007-2008) Distributed System Topics –Remote Procedure Call –Naming –Security and Encryption –Atomic Transactions –…

7. IntroductionCS-4513 D-term 20087 Textbook and Web Textbook:– –Distributed Systems: Principles and Paradigms, Tanenbaum and Van Steen, Prentice-Hall, 2007 Supplemental:– You should own or have access to one of the following from CS-3013 –Operating Systems Concepts, 7 th ed, by Silberschatz, Galvin, and Gagne, John Wiley and Sons, 2005 –Modern Operating Systems, 2 nd edition, by Andrew S. Tanenbaum, Prentice Hall, 2001 Course Information: –http://www.cs.wpi.edu/~cs4513/d08/http://www.cs.wpi.edu/~cs4513/d08/

8. IntroductionCS-4513 D-term 20088 Prerequisites Prerequisites:– –CS-3013, Operating Systems, or equivalent –C and C++ programming, esp. “low level” programming –Data structures pointers, linked lists, malloc(), free() –Unix/Linux user experience and access

9. IntroductionCS-4513 D-term 20089 Co-Requisite CS-4514, Computer Networks or CS-502, Operating Systems (graduate level) or Tutorial by R. Skowyra Sockets Connections OSI 7-layer model

10. IntroductionCS-4513 D-term 200810 Schedule & Logistics Schedule –Goddard Hall 227 –8:00 – 9:50 AM –Tuesdays & Fridays thru April 29 –No class on April 15 –14 classes total Exams –Mid-term on ~April 1 –Final on April 29 Unannounced Quizzes –May occur at any time –May be at beginning, middle, or end of class Mobile Phones, pagers, laptops, and other devices OFF during class Two Programming Projects –Fossil Lab –One individual, one team Office Hours –Adjunct Office, Fuller 239 –by appointment, or –Normally ½ hour after class Teaching Assistant –Rick Skowyra –Isaac Chanin Contacts – @ cs.wpi.edu –Adjunct office phone: (508) 831-6470 (shared, no messages) –cs4513-staff at same domain

11. IntroductionCS-4513 D-term 200811 Grading –Exams – 40% –Programming Projects – 40% –Class participation, homework, & quizzes – 20% Unless otherwise noted, assignments are to be completed individually, not groups Late Policy – 10%/day –But contact Professor for extenuating circumstances at least one day prior to deadline or exam date WPI Academic Honesty policy

12. IntroductionCS-4513 D-term 200812 Miscellaneous Is this course the capstone for a Minor in CS? Anyone needing a project for BS & MS credit? How many students feel they need tutorial on networking Scheduling options

13. IntroductionCS-4513 D-term 200813 Project Work Two project One individual – Remote Procedure Call One team – Choice of Distributed or File System topics Fossil Lab Newly refurbished Your accounts Virtual machines

14. IntroductionCS-4513 D-term 200814 Cloning a Virtual Machine Log in using Fossil password Navigate to P drive Open Clonable-SUSE-Linux-10.3 Double-click on VMware configuration file Select “Clone this virtual machine” Root and “student” password Fossil-B17 Linked vs. Full clone Linked – about 2-3 gigabytes, tied back to master Full – 8-9 gigabytes, can stand alone –Exceeds your quota on Fossil server

15. IntroductionCS-4513 D-term 200815 Questions?

16. IntroductionCS-4513 D-term 200816 Ground Rule There are no “stupid” questions. It is a waste of your time and the class’s time to proceed when you don’t understand the basic terms. If you don’t understand it, someone else probably doesn’t, either.

17. IntroductionCS-4513 D-term 200817 Instructor — Hugh C. Lauer Adjunct Professor Ph. D. Carnegie-Mellon 1972-73 –Dissertation “Correctness in Operating Systems” Lecturer: University of Newcastle upon Tyne, UK Approximately 30 years in industry in USA Research topics –Operating Systems –Proofs of Correctness –Computer Architecture –Networks and Distributed Computing –Real-time networking –3D Volume Rendering –Surgical Simulation and Navigation –…

18. IntroductionCS-4513 D-term 200818 Systems Experience IBM Corporation University of Newcastle Systems Development Corporation Xerox Corporation (Palo Alto) Software Arts, Inc. Apollo Computer Eastman Kodak Company Mitsubishi Electric Research Labs (MERL) Real-Time Visualization Founded and spun out from MERL Acquired by TeraRecon, Inc. SensAble Technologies, Inc. Dimensions Imaging, Inc. (new start-up)

19. IntroductionCS-4513 D-term 200819 VolumePro™ Interactive volume rendering of 3D data such as MRI scans CT scans Seismic scans Two generations of ASICs, boards, software VolumePro 500 – 1999 VolumePro 1000 – 2001 CTO, Chief Architect of VolumePro 1000 7.5-million gate, high-performance ASIC 10 9 Phong-illuminated samples per second

20. IntroductionCS-4513 D-term 200820 Sample images from VolumePro

21. IntroductionCS-4513 D-term 200821 Operating Systems I have known IBSYS (IBM 7090) OS/360 (IBM 360) TSS/360 (360 mod 67) Michigan Terminal System (MTS) CP/CMS & VM 370 MULTICS (GE 645) Alto (Xerox PARC) Pilot (Xerox STAR) CP/M MACH Apollo DOMAIN Unix (System V & BSD) Apple Mac (v.1 – v.9) MS-DOS Windows NT, 2000, XP various embedded systems Linux …

22. IntroductionCS-4513 D-term 200822 Other Two seminal contributions to computer science Duality hypothesis for operating system structures (with Roger Needham) First realization of opaque types in type-safe programming languages (with Ed Satterthwaite) 21 US patents issued Computer architecture Software reliability Networks Computer graphics & volume rendering

23. IntroductionCS-4513 D-term 200823 Class Discussion (laptops closed, please) What is Distributed Computing?

24. IntroductionCS-4513 D-term 200824 Distributed System Collection of computers that are connected together and (sometimes) interact Many independent problems at same time Similar Different Or … –One very big problem (or a small number) Computations that are physically separated Client-server Inherently dispersed computations

25. IntroductionCS-4513 D-term 200825 Distributed Computing Spectrum Many independent computations at same time Similar — e.g., banking & credit card; airline reservations Different — e.g., university computer center; your own PC Or … –One very big problem (or a few) Computations that are physically separated Client-server Inherently dispersed computations

26. IntroductionCS-4513 D-term 200826 Multiprocessing  Distributed Computing (a spectrum) Many independent problems at same time Similar — e.g., banking & credit card; airline reservations Different — e.g., university computer center; your own PC Or … –One very big problem (too big for one computer) Weather modeling, Finite element analysis; Drug discovery; Gene modeling; Weapons simulation; etc. Computations that are physically separated Client-server Inherently dispersed computations

27. IntroductionCS-4513 D-term 200827 Multiprocessing  Distributed Computing (a spectrum) Many independent problems at same time Similar — e.g., banking & credit card; airline reservations Different — e.g., university computer center; your own PC Or… –One very big problem (too big for one computer) Weather modeling, Finite element analysis; Drug discovery; Gene modeling; Weapons simulation; etc. Computations that are physically separated Client-server Dispersed – routing tables for internet; electric power distribution.

28. IntroductionCS-4513 D-term 200828 Observation Same spectrum applies to multiprocessor systems –Much more tightly coupled that traditional “distributed systems” Some differences –“Multiprocessor systems” Usually under same management, often in same room Very fast communication –“Distributed systems” Sometimes not under same management Slower communication

29. IntroductionCS-4513 D-term 200829 Another Observation (attributed to R. Hamming) When you change the operating point of a system by an order of magnitude … … you introduce qualitative changes in how to approach problems

30. IntroductionCS-4513 D-term 200830 Observation Same spectrum applies to multiprocessor systems –Much more tightly coupled that traditional “distributed systems” Some differences –“Multiprocessor systems” Usually under same management Very fast communication –“Distributed systems” Sometimes not under same management Slower communication So there is a qualitative difference in how we approach these two kinds of systems

31. IntroductionCS-4513 D-term 200831 Let’s look at an example An inherently distributed computation –I.e., parts of the computation must occur at physically separate locations –Under separate administrations Internet routing tables

32. IntroductionCS-4513 D-term 200832 The Internet A vast collection of independent computers –~ 600  10 6 All connected together Any computer can send a message to any other Messages broken up into little packets Question: how do packets find their way to destinations?

33. IntroductionCS-4513 D-term 200833 Internet

34. IntroductionCS-4513 D-term 200834 Distributed routing algorithm (simplified example) Each node “knows” which networks are directly connected to it. Each node maintains table of distant networks [network #, 1 st hop, “distance”] Adjacent nodes periodically exchange tables Update algorithm (for each network in table) If (my distance to network > neighbor’s distance to network + my distance to neighbor), then … … update my table entry for that network so that neighbor is first hop.

35. IntroductionCS-4513 D-term 200835 Distributed routing algorithm (result) All nodes in Internet maintain reasonably up-to-date routing tables Rapid responses to changes in network topology, congestion, failures, etc. Very reliable with no central management!

36. IntroductionCS-4513 D-term 200836 Characteristic The routing algorithm is inherently distributed Different parts execute in physically separated locations Only nearby nodes “know” whether –Neighbors are up or down –Networks are congested or not

37. IntroductionCS-4513 D-term 200837 Big networks Network management systems Monitoring health of network (e.g., routing tables) Identifying actual or incipient problems Data and statistics for planning purposes

38. IntroductionCS-4513 D-term 200838 Next Topic Questions?